论文标题
用EAMV1进行的当今气候模拟中的量化和归因时间步骤灵敏度
Quantifying and attributing time step sensitivities in present-day climate simulations conducted with EAMv1
论文作者
论文摘要
这项研究评估了使用1度水平分辨率的能源Exascale Exerage Exersystem System System Model 1（EAMV1）进行的当今气候模拟中时间整合误差的相对重要性。我们表明，在模型的所有主要部分中，6的时间步长的降低会导致长期平均气候的重大变化。这些变化表明，减少时间截断误差导致了显着的，尽管在模拟和观察到的当前气候之间的一致性不足以降低；在没有这些截断误差的情况下，该模型将需要重新调整以恢复最佳的气候保真度。时间步长灵敏度的粗粒归因是通过在EAM的各个组件中分别缩短时间步长或通过修改某些过程之间的数值耦合来实现的。结果提供了有用的线索，以帮助更好地了解EAM中时间步长灵敏度的根本原因。这里使用的实验策略还可以为其他模型提供识别和减少时间整合错误的途径。
This study assesses the relative importance of time integration error in present-day climate simulations conducted with the atmosphere component of the Energy Exascale Earth System Model version 1 (EAMv1) at 1-degree horizontal resolution. We show that a factor-of-6 reduction of time step size in all major parts of the model leads to significant changes in the long-term mean climate. These changes imply that the reduction of temporal truncation errors leads to a notable although unsurprising degradation of agreement between the simulated and observed present-day climate; the model would require retuning to regain optimal climate fidelity in the absence of those truncation errors. A coarse-grained attribution of the time step sensitivities is carried out by separately shortening time steps used in various components of EAM or by revising the numerical coupling between some processes. The results provide useful clues to help better understand the root causes of time step sensitivities in EAM. The experimentation strategy used here can also provide a pathway for other models to identify and reduce time integration errors.
